*{
    padding: 0;
    margin: 0;
}
input{
    width: 80px;
    height: 30px;
    border: 1px solid black;
    margin: 20px 0 0 20px;
}
/*.main{*/
    /*display: none;*/
/*}*/
.big_box{
    width: 100%;
    height: 100%;
    background: #7e7b7a;
    opacity: 0.5;
    /* 兼容IE */
    filter:alpha(opacity=30);
    /*display: none;*/
    position: fixed;
    top: 0;
}
.middle_box{
    width: 800px;
    height: 400px;
    background-color: white;
    border-radius: 5px;
    border: 0 ;
    left: 50%;
    top: 50%;
    margin-top: -200px;
    margin-left: -400px;
    box-sizing: border-box;
    padding: 10px;
    /*opacity: 1;*/
    font-size: 20px;
    color: #343434;
    text-align: center;
    overflow: hidden;
    position: fixed;
}
.middle_box p{
    margin: 190px 0 0 0 ;
    
}
.middle_box .small_box{
    width: 780px;
    height: 50px;
    padding: 10px;
    background: #3865ef;
    border: 0;
    border-radius: 5px;
    text-align: left;
    font-size: 20px;
    line-height: 30px;
    color: white;
    box-sizing: border-box;
    /*opacity: 1;*/
    position: absolute;
    margin: 0 10px 0 0 ;
}
.small_box label{
    width: 26px;
    height: 26px;
    background: white;
    color: #000;
    text-align: center;
    font-size: 20px;
    position: absolute;
    right: 10px;
    top: 12px;
    border-radius: 5px;
    line-height: 26px;
}
.middle_box .footer {
    text-align: center;
    font-size: 16px;
    line-height: 20px;
    color: #3a3a3a;
    margin-top: 120px;
}
span{
    color: red;
}